The attack is significant for reasons beyond the saddening and unprecedented death toll. First, the attack occurred in the northern stronghold of Atta Mohammad Noor, the governor and warlord of Balkh province. Mazar-i-Sharif had been among the most secure cities of the country. The base, which I have visited several times, is on the city’s outskirts. Noor has many political opponents, raising questions about possible collusion with the Taliban attack.

Second, the attack, which was carried out by gunmen in stolen Afghan Army uniforms and kit, reportedly had insider assistance. General John “Mick” Nicholson has long complained about the corruption and poor leadership within the Afghan military and police. This event is a shocking consequence of these problems – problems that are sapping the readiness and combat performance of the Afghan security forces much faster than the U.S. military can build them.